When his brother catches measles, Tom is sent away for the summer to stay with his uncle and aunt and is thoroughly fed up about it. What a boring summer it's going to be. But then, lying in bed one night, he hears the old grandfather clock in the hall strike the very strange hour of 13 o'clock. What can it mean? As Tom creeps...
The first message sent to Tom Thorne's phone was just a picture - the blurred image of a man's face, but Thorne had seen enough dead bodies to know that the man was no longer alive. But who was he? Who sent the photograph? And why? While the technical experts attempt to trace the sender, Thorne searches the bulletins for a reported death that matches the photograph. Then another picture arrives.